Insulating flexible composite element

ABSTRACT

An improved heat and cold insulating flexible composite element comprises at least one radiation chamber with walls of flexible material having reflecting surfaces. Opposite walls of said chamber are resiliently spaced from each other by suitable spacing elements. Preferably the chambers are enclosed by an envelope which may also be formed of flexible reflecting sheets.

United States Patent 1191 Becker 1111 3,811,239 May 21, 1974 1 1 INSULATING FLEXIBLE COMPOSITE ELEMENT [76] Inventor: Otto Alfred Becker,

Robert-Koch-Strasse, 59, 66 Saarbruecken, 6 Germany 22 Filed: Mar. 18,1971

211 Appl.No.: 125,549

[30] Foreign Application Priority Data Mar. 19,1970 Germany 2013115 Feb. 19, 1971 Germany 2108110 [52] C1 52/406, 52/619, 52/173, I 52/615, 161/113 [51] Int. Cl E04b 2/28, E046 2/34 [58] 'Field of Search 52/172, 303, 309, 404, 52/406, 615, 618; 161/117, 119, 113, 68, 44

[56] References Cited 1 UNITED STATES PATENTS 1,917,456 7/1933 Miekelson 161/113 1,956,323

4/1934 Gregg 52/618 X 2,175,630 10/1939 Kiesel 52/404 2,662,043 12/1953 Clements 52/404 x 2,934,465 4/1960 Warp 52/404 x 3,540,615 11/1970 Paine et 31.... 52/404 x 3,646,721 3/1972 Becker 52/309 x 3,604,163 9/1971 McCurdy 52/172 3,649,430 3/1972 Lewis et al 161/113 x FOREIGN PATENTS OR APPLICATIONS 890,995 3/1962 Great 13111616.... 52/404 6,802,872 9/1968 Netherlands 52/406 Primary ExaminerAlf red C. Perham Attorney, Agent, or FirmErich M. H. Radde ABSTRACT An improved heat and cold insulating flexible composite element comprises at leastone radiation chamber with walls of flexible material having reflecting surfaces. Opposite walls of said chamber'are resiliently spaced from each other by suitable spacing elements.

Preferably the chambers are enclosed by an envelope which may also be formed of flexible reflecting sheets.

4 Claims, 6 Drawing Figures PATENTEDIAYEI m4 3311.239

SHEET 1 0F 2 FIG. I

INVENTOR. or T0 ALF/QED BECKER BY 1AM.

Assn/r PATENTEDIAYZI mm 3.81 1.239

SHEET 2 BF 2 FIG. 5

I .I J

47 FIG. 6

INVENTOR.

, OTTO ALFRED 8CK5 BY 11m A Asa- BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to flexible composite elements and more particularly to flexible composite elements useful as heat and cold insulating structures of improved heat and cold insulating power.

2. Description of the Prior Art Flexible composite elements have been made and used heretofore to provide heat or cold insulation. Such elements composed of textile fabrics, wool, plastic foam material, and the like have been employed as material for curtains, blinds, and shades, tents, and the like as well as for wall and floor coverings, ceilings, and the like structural material, and also for cushions, bed covers, articles of clothing, and the like. The known flexible'composite elements of this type, however, did not fully meet the requirements of satisfactory heat and cold insulation.

SUMMARY OF THE INVENTION It is, therefore, an object of the present invention to provide flexible composite elements of considerably improved heat and cold insulating power.

Other objects of the present invention and advantageous features thereof will become apparent as the description proceeds.

Said objects of the present invention are achieved by preventing the transfer of thermal energy by heat radiation by means of highlyreflective, metallized reflector foils and radiation chambers associated with them, while substantially limiting thermal conduction. As 'reflectorfoils there are preferably used thin, flexible plastic sheets with pure-metal aluminum coatings applied by vacuum vaporization. They reflect the heat rays impinging them to the extent of about 90 percent and radiate off only about 10 percent of the energy taken up. By flexible, insulating spacers, consisting preferably of soft. elastic plastic foam blankets which are perforated or slit and then expanded, radiation chambers for the reflector sheets are formed. By the perforating or slitting of the insulating agent, the chamber walls are reduced to thin foam ribs. The chambers are small and tightly sealed-off so that no convection of the air can take place.

A single flexible reflector sheet and an insulating blanket forming radiation chambers are by themselves sufficient to obtain a good insulation. Insulating chambers can also be arranged on both sides of the reflector sheet, or else insulating chambers can be closed-ofl by sheets on both sides, after which one insulating cham ber and one reflector sheet each can alternately follow. In this way highly effective insulations are obtained. 1 Since heat reflection is practically eliminated by precipitation of water of condensation of the reflector sheets, it is advisable, depending on the nature of the use ofthe flexible composite element, to close the composite element off hermetically from the outside. This can be effected in the manner that the outer reflector sheets which bear the insulating agent, reflector sheets, and radiation chambers between them are combined with each other to form a hermetically closed envelope,

sheath. or casing. Dry air or a dry gas, for instance, ni-

tically impervious to vapor. Such reflector envelopes can in addition be protected from mechanical injury by another envelope, for instance, by an envelope of articifical leather or an envelope of other decorative sheets or, for instance, of tent cloth, preferably with the interposition of a wide-mesh fabric, or perforated, soft plastic foam. The hermetically closed flexible envelopes can be provided with valves which make possible filling or renewal of the dry air or of a gas at any time. Furthermore, replaceable, hermetically arranged, perforated plastic tubes filled with air-drying substances, for instance, calcium chloride, can also be introduced into the flexible composite elements. This can be effected, for instance, with perforated double tubes, one of which, extending towards the inside of the composite element, is hermetically sealed and joined to the hermetically closed envelope, while the other tube is inserted thereinto in replaceable fashion and in such a manner that it is sealed off hermetically against the outside.

It is advantageous to be able to stretch or tension the composite elements, for instance, tent cloths, wall coverings, and the like, in order to hold the reflector sheets spaced apart by the chamber ribs.

This can be effected in many different manners. For

this it is advisable to tension the envelopes, for instance, by stiffening or reenforcing means,which are introduced detach'ably in frame-like fashion into the edge portion of the envelopes which are folded over. By tensioning the envelope, the innerelements, and

particularly the reflector-sheets and spacerswhich are preferably fastened on top and on bottom and, if desired, on the sides with tension springs or rubber bands or the like, are also tensioned if their sizeis maintained correspondingly smaller than that of the envelope.

Fine nettings of insulating material can also be provided on both sides of the flexible spacers and they may preferably also be tensioned so as to secure the chambers from penetration of the reflector sheets.

When using the composite elements for building pur-' poses, the individual envelopes can be connected to each other by tubular conduits which are, for instance, connected via a main conduit with an air-drying system. This air-drying system permits the inward and outward flow of the air contained in the envelopes. As a result thereof newly entering atmospheric air has its moisture content reduced by the air-drying system to such anextent that no water of condensation can form. Protection against dust canalso be obtained by means of suitably provided filters. This system can also be combined with an air pump to maintain the pressure in the flexible composite element as well as to pump outer air via the dust filter and the drying system into the composite element in the form of dry air. Thereby, the lighter, moist air present at the upper end of the composite element is discharged through an outlet valve preferably arranged atsaid upper end.

Air circulation can also be provided by connecting the upper valve tube with the pump system.

The volume of the envelope is dimensioned so large that the air on the inside can expand, upon heating, without change in pressure. The sheets can, for instance, be firmly connected at their edges with the spacer means.

All parts, for instance, the fabric, the plastic foam, and the like of the composite element can be vaporcoated on all sides withaluminum so as to reflect.

DESCRIPTION OF THE DRAWINGS I In said FIGS. like numerals designate like parts of the composite elements of this invention.

DESCRIPTIONOF PREFERRED EMBODIMENTS OF THE INVENTION FIG. lshows in vertical cross-sectional view two reflector sheets or foils l and 2 consisting, for instance, of plastic sheets both of the surfaces of which have been vapor-coated in a vacuum with a highly reflective layer of aluminum. Aperforated or slit and expanded plastic foam cover 3 is arranged between the two reflector sheets 1 and 2 as spacer means forming insulating small radiation chambers 4; The reflector sheets 1 and 2 which preferably consist of plastic material coated by vaporization with aluminum on both sides, are connected and welded at their edges-in air and vapor-impervious manner to form an envelope or casing. The inner air is displaced and replaced by predried air through valves Sand 6. For the protection of the envelope formed bysheets 1 and 2'and to prevent deposition of dust and precipitation of water of condensation, it is surrounded on all sides by a wide-mesh, gridshaped fabric 7 and 8. Instead ofa fabric, there can also be used, for instance, a flexible plastic foam sheet with or-without perforations, and when'not perforated, with strongly pro-filed surfaces, for instance, with protruding ribsextending in opposite directions on the two surfaces. This composite element is closed off and sealed on all sides from the outside by further similar or, for instance, decoratively printed plastic sheets or foils- 9 and theedges of which are also connected and sealed to form a hermetic envelope. In this connection the inner surfaces of the sheets 9 and 10 can also be coated by vapor deposition with highly-reflective aluminum. The grid-shape'd'fabrics 7 and 8 thereby form radiation chambers containing quiescent air. At the same time they assure the spacing between the reflector sheets. All parts of the composite element are flexible. In this way changes'in air pressure and temperature can be accommodated by corresponding change in volume. If the second envelope formed by sheets 9 and 10 also consists of reflector sheets coated with aluminum by vapor deposition, a third replaceable'decorative envelope (not shown) can be provided. Depending on the purpose which this composite element is to serve, for instance, as insulating covering for the walls of rooms, it may be advisable to connect the individual composite elements with a main pipeline or a hose line which in its turn is connected with an airdrying system. In this way, in case of change of volume in the envelope 1 and 2,.air can escape via the drying system and. conversely, in case of cooling, dried air can be supplied again via the drying system to the envelope.

The air-drying system can consist, for instance, in known manner of a housing with insertable screens to receive air-drying agents, for instance, calcium chloride. Air cooling units of known type can also be provided for the removal of water vapor either alone or in addition. Valves can be associated with the composite element and the air-drying system. Thus, for instance, an upper valve can open upon an increase of the 'pressure in the composite element and a lower valve incase of a decrease of the pressure can allow additional air to enter via the air-drying system.

FIG. 2 shows the sequence of the layers of the composite element, commencing with the outer, for instance, decorative, protective sheet 9 and' terminating with the opposite protective sheet 10. The top view of the foam cover 3 shows the expanded slits or the radiation chambers 4 formed thereby.

FIG. 3 is identical to FIG. 1, except for the insertion of a foam cover 13 forming further radiation chambers 12 and another reflector sheet 11 which is hermetically sealed to the reflector sheet 1 along the entire edge. There can be provided as required any desired number of insulating groups consisting of reflector sheets 1 and 2 and the spacer means forming radiation chambers 4 and 12 to increase the insulating effect.

The thin reflector sheets or foils and the fine surface coatings with vapor-deposited aluminum are of no special importance with respect to the heat conduction, despite the fact that the edges of the sheets or foils are joined to each other.

The same applies also to the outer' sheet 9 and 10. The very soft foam layers 3 and 13 which are reduced to thin ribs, also conduct the heat to only a very slight and inconsiderable extent. Convectioh of the quiescent dry air enclosed in the chambers 4 and 12 is also practically excluded for energy transfer. The depth of the chambers 4 and 12 is preferably only about l0 mm. The wide-mesh, grid-shapedouter fabric 7 and 8 also composed of insulating material, transfers the heat from the outer sheet to the inner sheet only to a slight extent. If the foam coversor layers 3 and 13 and thefabric 7 and 8 are also vapor-coated with aluminum, then the insulating effect is further increasedby reflection. The grid-shaped fabric 7 and 8 can also be made of other material, for instance, of rubber or cords or th like.

FIG. 4 shows in vertical cross-section the inner envelope of a flexible composite element having the envelope sheets 1 and 19 and the reflector sheets '2, 11, and 16 arranged between the spacers 3, 13, I4, and 17 and the chambers 4, l2, l5, and 18. The reflector sheets 2, 1 1,and 16 are held tight by springs 20 which act via clamps 21 on the lower sheet edge. The spacers 3, l3, l4, and 17 can also be tensioned in the same manner.

FIG. 4 shows a lower tube 22 which is provided with perforations 23 for the passage of dry air. At the upper end of the-element there is inserted tube 24 with perforations 25, as well as valve 26 through which moist air can be let out.

The lower tube 22 is connected with an air-drying system 29 in front of which there is provided a dust filteringsystem 30. In addition there can be provided a pump 31 which draws in air via valve 32 and forces the air into the composite element via the dust filter 30 and the air-drying system 29. Since the moist air is lighter than dry air, it-rises upward in the composite element and is forced out through valve 26 by the dry air entering at the bottom.

FIG. 5 shows the lower part of a tubular insert 33 which preferably is perforated towards the top and thereby allows the air to enter the inside of the tube. In this tube there is arranged a second tube 34 which also has corresponding perforations and contains air-drying agents, for instance, calcium chloride. The outer tube 33 is hermetically sealed to the envelope 19 and the inner tube 34 is provided with a closure cover 35 and an elastic part 36 which rests in hermetically sealing manner in a gasket 37.

In addition, an inlet valve 38 can also be provided at the lower part and an outlet valve in corresponding manner on the upper part. This for the purpose of filling the element in advance withdry air.

The pump can be omitted. Instead of it, there can be an open connection with the atmosphere.

Another possibility consists of connecting the upper tube 24 with the air pump by means ofa corresponding length of tube and thus effecting circulation of air by the pump within the element, the moisture being removed from the moist air by the air-drying agents in the air-drying system 29.

FIG. 6 shows an insulating group within a composite tal bars or reenforcements. These embodiments of the present invention are especially suitable for tents, wall and ceiling coverings, and floor coverings.

element consisting of the reflector sheet 2, followed by a supporting netting 40; below the latter the chamberforming spacer 13, and following the latter in its turn a supporting netting 41 and following same finally the sheet 11.

By the arrangement of the supporting nettings 40 and 41 on both sides'of the spacer 13, a sinkingof the reflector sheets 2 and 11 into the spacing spaces of the radiation chambers is substantially prevented. This all the more effectively since by the tensioning of the reflector sheets and spacers, as well as the supporting nettings, the radiation space is kept free. Tensioning of the spacers, the supporting nettings, etc., is achieved by providing rubber bands 47 which pull said spacers, supporting nettings, etc. tautly apart towards all sides.

In order to be able to effect tensioning of the flexible composite element, stiffening or reenforcing of its edge parts is required. For this purpose the plastic envelopes are so sealed in accordance with FIG. 4 that they form folds 27 into which bars, strips 28, or the like can be inserted. In the same manner, folds are also arranged in vertical direction, said folds being also provided with bars, strips, or the like, and being firmly connected in a frame-like but detachable manner with said horizon- I claim:

1. An insulating flexible composite element comprising at least one radiation chamber with walls of flexible material having reflecting surfaces, opposite walls of said chamber being resiliently spaced from each other in a shape retaining manner by at least one flexible spacing element of a perforated soft, elastic, heatinsulating material, the perforations forming the radiation chamber with the walls of flexible material, said radiation chamber with its reflecting walls and spacing element being enclosed by at least one flexible envelope hermetically sealing said chamber and spacing element and forming a unitary part of the insulating flexible composite element; the edge portions of the walls of the radiation chamber, the spacing element, and the envelope being provided with stiffening means causing tensioning of said walls, spacing element, and envelope, said stiffening means being inserted into folds formed by the envelope enclosing the reflecting walls and spacing element of the composite insulating element;

2. The insulating flexible composite element of claim l, in which the stiffening means are strips.

3. The insulating flexible composite element of claim 1, in which the stiffening means are .bars.

.4. An insulating flexible composite element comprising at least one radiation chamber with walls formed of sheet material having surfaces which reflect into said chamber, opposite walls of said chamberbeing resiliently spaced from each other in a shape retaining manner by at least one flexiblespacing element of a perfo rated soft, elastic, heat-insulating material, the'perforations forming the radiation chamberwith the walls of flexible material, supporting means arranged between the reflecting sheets and the spacing element, said radiation chamber with its reflecting walls and spacing element being enclosed by at least one flexible envelope hermetically sealing said chamber and spacing element and forming a unitary part of theinsulating flexible composite element; the edge portions of the walls of the radiation chamber, the spacing element, the envelope, and thesupporting means being-provided with stiffening means causing tensioning of said walls, spacing element and supporting means, said stiffening means being inserted into folds formed by-the envelope enclosing the reflecting walls and spacing element of the composite insulating element. 

1. An insulating flexible composite element comprising at least one radiation chamber with walls of flexible material having reflecting surfaces, opposite walls of said chamber being resiliently spaced from each other in a shape retaining manner by at least one flexible spacing element of a perforated soft, elastic, heat-insulating material, the perforations forming the radiation chamber with the walls of flexible material, said radiation chamber with its reflecting walls and spacing element being enclosed by at least one flexible envelope hermetically sealing said chamber and spacing element and forming a unitary part of the insulating flexible composite element; the edge portions of the walls of the radiation chamber, the spacing element, and the envelope being provided with stiffening means causing tensioning of said walls, spacing element, and envelope, said stiffening means being inserted into folds formed by the envelope enclosing the reflecting walls and spacing element of the composite insulating element.
 2. The insulating flexible composite element of claim 1, in which the stiffening means are strips.
 3. The insulating flexible composite element of claim 1, in which the stiffening means are bars.
 4. An insulating flexible composite element comprising at least one radiation chamber with walls formed of sheet material having surfaces which reflect into said chamber, opposite walls of said chamber being resiliently spaced from each other in a shape retaining manner by at least one flexible spacing element of a perforated soft, elastic, heat-insulating material, the perforations forming the radiation chamber with the walls of flexible material, supporting means arranged between the reflecting sheets and the spacing element, said radiation chamber with its reflecting walls and spacing element being enclosed by at least one flexible envelope hermetically sealing said chamber and spacing element and forming a unitary part of the insulating flexible composite element; the edge portions of the walls of the radiation chamber, the spacing element, the envelope, and the supporting means being provided with stiffening means causing tensioning of said walls, spacing element and supporting means, said stiffening means being inserted into folds formed by the envelope enclosing the reflecting walls and spacing element of the composite insulating element. 